Cutaneous pigmented lesions are extremely common in dermatology. Although the majority of these lesions are benign, the possibility of malignant transformation in addition to cosmetic considerations have frequently necessitated their therapeutic removal. The laser could be appropriately adapted to selectively destroy only pigment cells while minimizing injury to surrounding structure, thus providing a less traumatic alternative with reduced scarring to surgical excision or dermabrasion. Candela Laser Corporation and Boston University School of Medicine will conduct in vivo studies employing pig skin to determine the optimum laser operating parameters of wavelength, energy density and pulse duration for effective treatment of pigmented lesions. Candela proposes to develop a flashlamp excited dye laser and a solid state laser for this study and compare the merits of each in the treatment of pigmented lesions. If successful, clinical trials and prototype product development will be undertaken in Phase II.